The present invention relates to a cutting tool including a tool holder having a recess for receiving a cutting insert and separate means to fasten the cutting insert to the tool holder.
More specifically, the means consists of a locking pin that has a combined tilting and linear movement, being actuated by a locking screw.
A number of solutions are known to secure a cylindrical holed insert in a tool holder using a clamping pin, which presses the insert against the lateral sides of a holders pocket, on a direction parallel with bottom side of the pocket, such as in the U.S. Pat. Nos. 3,280,450; 3,289,272; 3,314,126; 3,409,964; 3,469,269.
In this kind of solutions the stability of insert in its pocket against unwanted lifting is given by the friction between the insert surfaces in contact with the pin or holder. Some of those solutions do not provide the means for shim installing and that makes the insert more vulnerable. While for relatively light machining jobs the above can be acceptable mostly due to some advantages like no restriction for chip flowing and easy exchange of insert, it can not cover heavy-duty machining situation, when big cutting forces combined with vibration may insecure the insert. For such situation a tool construction has been developed when, in addition to the pin an extra clamping device was added which presses the insert from the above, like in U.S. Pat. Nos. 3,837,058; 3,889,332; 4,938,639.
Those solutions give a strong and secure clamping job but with the disadvantages of chip flow obstruction and more difficult insert replacing.
Compromise solutions have been developed when the clamping element is a pin that can apply the clamping force in both horizontal and vertical direction, such in the U.S. Pat. Nos. 3,341,923; 3,908,255; 4,011,049; 4,427,322; 4,615,650; 4,632,593; 4,869,624; 4,890,961; 5,199,828; 6,155,754; 6,582,162; 6,599,060; 6,773,210.
Some of the above solutions are applicable at countersink hole inserts only with the disadvantage that either in some of them the clamping element that is usually a screw has to be removed in order to replace the insert and can be easily lost or in some of them the arrangement is complicated by the additional elastic elements like springs, clips, tubular pins or rubber rings.